The present invention relates to a light weight responsive tilt ramp rodent trap.
FIGS. 7 and 8 show a typical prior art tilt ramp trap. This trap is of the type manufactured under the trademark TIN CAT® by Woodstream Corporation, Lititz, Pa. 17543. The prior art trap is designated generally by the numeral 100. It includes a box 102 which encloses a trap compartment 104. Providing entrance into the trap compartment 104 is a mouse hole 106. Within the box 102 is a tube 107 having a tube entrance opening 108 adjacent the mouse hole 106 and having a tube exit opening 110 providing communication into the trap compartment 104.
Within the tube 107 is a tilt tramp 112. Tilt ramp 112 pivots about a ramp or pin axis 114 and includes an entrance end 116 and an exit end 118. A counter weight 120 is provided on the entrance end 116 to bias the tilt ramp 112 to the position shown in FIG. 7.
A flap 122 is pivoted about a pivot pin 124 and rests by gravity on the entrance end 116 of tilt ramp 112.
When a mouse enters into the mouse hole 106, the mouse M proceeds up the ramp, and when the weight of the mouse at 1 5/16th inches from the pivot point or pin axis 114 exceeds 7 grams, the ramp tilts downwardly to the position shown in FIG. 8. At the same time the flap 122 pivots upwardly in response to frictional engagement with the end 116 of tilt ramp 112.
The above prior art device has several shortcomings. The weight of 7 grams at a distance of 1 5/16th inches from the fulcrum or pin axis 114 of the tilt ramp 112 is sufficient to cause the ramp to tilt in response to a full sized adult mouse, but is insufficient to tilt in response to a lighter weight of an immature mouse. Thus younger mice can proceed up the ramp without tilting the ramp and escape merely by returning down the ramp.
This responsiveness to 7 grams of weight is the result of several factors. One factor is the chosen weight of the counterweight 120. Another factor is the friction between the flap 122 and the entrance end 116 of the tilt ramp 112. As can be seen in FIG. 7, the flap 122 rests with its face in full engagement with the upper surface of the tilt ramp 112, and this adds to the friction required in order to tilt the tilt ramp 112. Also, there is a need to reduce the friction caused by the pin axis 114 and the pivot pin 124.
Therefore, a primary object of the present invention is the provision of an improved light weight responsive tilt ramp rodent trap.
A further object of the present invention is the provision of a light weight responsive tilt ramp rodent trap which includes a tilt ramp that tilts in response to a weight of 4 grams at a distance of 1 5/16th inches from the fulcrum of the tilt ramp.
A further object of the present invention is the provision of an improved light weight responsive tilt ramp rodent trap which includes dimples and tabs for engaging the flap as the tilt ramp pivots about its tilt ramp axis, thereby reducing the friction between the flap and the tilt ramp.
A further object of the present invention is the provision of an improved hinge for the tilt ramp which reduces the friction necessary to cause the ramp to tilt.
A further object of the present invention is the provision of an improved hinge for the flap which reduces the friction necessary for the flap to pivot in response to the tilting of the tilt ramp.
A further object of the present invention is the provision of an improved counter balance which reduces the force necessary to tilt the ramp.
A further object of the present invention is the provision of a trap which includes tubes for the mouse to enter which are connected to the top wall of the trap and are pivotal to a position wherein the tubes are outside the trap for cleaning of the trap.
A further object of the present invention is the provision of an improved rounded corner on the inside of the trap box to facilitate cleaning.
A further object of the present invention is the provision of elongated ribs on the top wall of the box for improving the strength thereof.
A further object of the present invention is the provision of an improved light weight responsive tilt ramp rodent trap which is economical to manufacture, durable in use, and efficient in operation.